Using the new grid.negate_depth() method (#95)

Note that this will only work after Parcels v3.1.1 is released and on conda. But create this PR now already so we don't forget to update the VirtualShip

Author: erikvansebille

environment.yml

@@ -3,7 +3,7 @@ channels:
   - conda-forge
 dependencies:
   - click
-  - parcels >3, <3.1.0
+  - parcels >3.1.0
   - pyproj >= 3, < 4
   - sortedcontainers == 2.4.0
   - opensimplex == 0.4.5

src/virtualship/expedition/input_data.py

@@ -97,7 +97,7 @@ def _load_default_fieldset(cls, directory: str | Path) -> FieldSet:
 
         # make depth negative
         for g in fieldset.gridset.grids:
-            g.depth = -g.depth
+            g.negate_depth()
 
         # add bathymetry data
         bathymetry_file = directory.joinpath("bathymetry.nc")
@@ -137,7 +137,7 @@ def _load_drifter_fieldset(cls, directory: str | Path) -> FieldSet:
 
         # make depth negative
         for g in fieldset.gridset.grids:
-            g.depth = -g.depth
+            g.negate_depth()
 
         # read in data already
         fieldset.computeTimeChunk(0, 1)
@@ -169,7 +169,7 @@ def _load_argo_float_fieldset(cls, directory: str | Path) -> FieldSet:
         # make depth negative
         for g in fieldset.gridset.grids:
             if max(g.depth) > 0:
-                g.depth = -g.depth
+                g.negate_depth()
 
         # read in data already
         fieldset.computeTimeChunk(0, 1)